### Object Variable Not Set while indexing

Function Interest_Declining_Balance(optional OB,optional pmt(),optional purchase(),optional Days() as integer, optional rate)
dim Balance as double
dim Balance_Due as double
dim Sum as integer
dim Interest as double
dim Months as double

```
for i = 1 to UBound(Days)
Balance = (OB + pmt(i,1)-purchase(i,1))*Days(i,1)
next i
for a = 1 to UBound(Days)
Sum = Sum + Days(a,1)
next a
Balance_Due = Balance / Sum
Months = Sum/30
Interest = rate/100
Interest_Declining_Balance = (Balance_Due*Interest*Months)
End Function
```

~~ ~~End Function